(PHP 7, PHP 8)
IntlChar::istitle — Check if code point is a titlecase letter
$codepoint): ?boolDetermines whether the specified code point is a titlecase letter.
true for general category "Lt" (titlecase letter).
codepointThe int codepoint value (e.g. 0x2603 for U+2603 SNOWMAN), or the character encoded as a UTF-8 string (e.g. "\u{2603}")
Returns true if
codepoint is a titlecase letter, false if not. Returns null on failure.
示例 #1 Testing different code points
<?php
var_dump(IntlChar::istitle("A"));
var_dump(IntlChar::istitle("a"));
var_dump(IntlChar::istitle("Φ"));
var_dump(IntlChar::istitle("φ"));
var_dump(IntlChar::istitle("1"));
?>以上示例会输出：
bool(false) bool(true) bool(false) bool(true) bool(false)